Apparatus for boxing-in impressions



Feb. 7, 1956 CARTER 2,733,508

APPARATUS FOR BOXING-IN IMPRESSIONS Filed March 29, 1954 j INVENTOR W X (QM 1 lav/Um 4/1 5,

ATTORNEYS in Figure 1;

United States PatentO APPARATUS FORBOXING JN IMPRESSIONS Andrew L. Carter, Nashville, Tenn. Application March 29', 1954, Serial No; 419,451 4 Claims. ((11. 32- 17 .step of making a model from the impression. In thisstep, model material such as plaster is poured into the impression and, in addition, is poured up over the top of the impression in. order. to reproduce; the contour of 'the topof the impression and to provide a substantial base which is necessary in working, with the model during the later. steps in the denture making process. Naturally, it is necessary to provide some sort of matrix or. flange around the impression to retain and shape the plaster .which is poured up over the top of the impression. The

usual practice in the formation of such matrix is to build by hand out of clay or wax a flange around the sides of the impression tray. It is easy to understand that such an uncontrolled hand operation is time-consuming and ,usually results in an imperfect model which must be diswill be readily understood by those skilled carded or extensively trimmed. Once the matrix has i been formed, the usual practice is to hold the boxed impression on a vibrator while the model material is poured.

It is an object of the present invention to provide apparatus for boxing-in impressions for dentures and the like which will facilitate the making of accurate models from such impressions and will take all impression trays. Another object of this invention is to provide boxing apparatus having means for quickly and accurately forming a matrix around an impression to provide for the making of more accurate models in less time and with less training than can be accomplished with the usual practice. Similarly, the present invention will reduce the amount of plaster required for the models by avoiding the waste of plaster resulting from the necessary discarding or extensive trimming of models made by the usual practice.

A further object of the invention is to provide boxing apparatus which may be conveniently held on a vibrator during pouring of the model material, and having means for securely attaching an impression tray to the apparatus so that the'motion imparted by the vibrator will be fully transmitted through the apparatus to the tray.

Other and further objects, features, and advantages will be apparent from the description which follows read in connection with the accompanying drawings in which:

Figure 1 is a perspective" view of one embodiment of, the boxing apparatus as assembled for use with an impression tray;

Figure 2 is a bottom plan view of the apparatus shown 2,733,508 Eitented Feb. 7 1956 2. Figure 3 is a sectionalview taken on the line 33 of Figure l;

Figure 4 is a top plan viewof the in Figure 1, with parts removed;

FigureS is a sectional view similar to Figure 3 but showing-a modified form of the invention; and

apparatus shown Figure 6 is a top plan view similar to Figure 4 but showing the modification of Figure 5.

Referring to Figure 1 the boxing apparatus comprises a plate orbase member indicated generally at '1, which plate is formed with a relatively widetray receiving portion Sand a narrower handle portion 5. Plate 1 also has a flange portion 7 extending upwardly from the forward end thereof and'preferably normal-thereto. In Figure 1 the boxing apparatus is shown assembled for use with an impression tray 8 for a lower denture. Tray 8 is seated on thetray receiving portion 3 and is adjustably secured to plate 1 in a manner which will be hereinafter described in detail. The boxing apparatus includes a strip f deformable material, such assolid rubber. or

rubberized fabric, which is seated on plate, 1 and curved. about tray 8 to form a matrix around the outside edge of the tray. The ends of strip 9 extendaround the front of flange 7 and the entire strip is held in place bythe rubbe; bands 11 and'12.

Any particular impression from which it is desired to make a model'would normally be contained in the channel formedby tray 8. The impression is not shown in the tray because its position is readily understandable andbecause it is not apart of the boxing apparatus. In

this connection it should be understood that the boxing apparatus ofthis invention is not limited to boxing in dental impressions but maybe use forboxing otherirnpressions having a shape which can be received on plate 1 andsurrounded by strip 9.

As previously stated, tray 8 is designed to make im pressions of the lowergum and teeth, and to facilitate such use is fitted with an offset handle 14 as-shown best in Figure 3, the handle and tray being connected by rivets 15. in order to accommodate such offset handle construction, an opening 16 is provided in plate 1 so that the bottom of tray 8 may be seated on the tray receiving portion 30f plate 1 with handle 14 extending below the plate. Tray 8 is securely held in position on plate 1 by means of screw 13 and wing nut 19. is provided in plate 1 for the reception of screw 18 in a manner which allows adjustment of tray 8 longitudinally of the plate. Washers 22 are used in the conventional manner, and spacer 23 is used to lower the bottom extremity of tray 8 to a position substantially flush with the top of plate 1. A small hole 25 is provided in handle portion'S for the purpose of hanging up the plate when not in use.

The manner of using the previously described boxing apparatus will now be described with reference to Fig ures 1 through 4. With strip 9 and bands 11, 12 removed, tray 8 containing a 'wax impression (not shown) is seated on plate 1 by inserting handle 14 through opening 16. Then screw 18, washers 22, spacer 23 and wing nut 19 are assembled as shown in Figure 3. Wing nut 19 is not tightened until tray 8 is adjusted relative to flange 7 so that the space between them will provide the desired margin at the flat end of the model. The space bounded by the inside edge of tray 8 is then 'filled in with modeling clay or with a preformed lingual block, and, if it is desirable for the model to have a margin around the outside edge of the impression, modeling clay or similar material, equal in width to the desired margin, is placed around tray 8. Deformable strip 9 is then seated on plate 1 with its central portion around tray 8 and its ends across the front of flange 7, substantially as shown in Figure 1. Finally rubber bands 11 and 12 are stretched An elongated slot 21 3 around strip 9 to secure it in place and to assure complete contact between the strip and tray 8 or any margin material placed around the tray. If desired, a small roll of modeling clay maybe pressed down around the outside of strip 9 where it joins plate 1 to help insure proper seating of the strip and to seal the joint between the strip and plate. The boxing apparatus is then grasped by portion 5 and held on a conventional vibratorwhile the plaster is poured into the'im'pression and to the desired height thereabove.

Figures 5 and 6 show a modified form of the invention which is used in the same manner as previously explained ifor the embodiment shownin Figures 1-4. The modified form includes a plate 1 which is exactly the same as plate 1 in so far as handle'portion 5, flange 7', elongated slot 21' and hole 25 are concerned.- As will be readily apparent from a comparison of Figures 4 and 6, the only difference between plate 1 and plate 1' is that the tray receiving portion 3' of plate 1' does not include opening 16. Plate 1 is particularly designed for use with impression trays having straight handles, one such tray 8 with a straight handle 14 being shown in Figure 5. Tray 8' is of the type which is used for taking impressions of the upper gum, teeth and roof of the mouth, and for this purpose does not require an ofiset handle.

Since handle 14' is straight, its entire length lies along the top of plate 1' as shown in Figure 5, thus removing the necessity for opening 16. The location of handle 14 would, however, interfere wi h the proper seating of strip 9, and to overcome this objection the embodiment of Figure 5 contemplates a strip 9 having a recess 27 shaped to accommodate handle 14'. Tray 8' is adjustably secured on plate 1' by means of screw 18 and wing nut 19', washers 22' being utilized as in the embodiment of Figures 14 and spacer 23 being unnecessary. Rubber bands 11' and 12' hold strip 9 in position around tray 8 in the same manner as bands 11 and 12 are employed in Figure 1. Except as otherwise noted, the modified form of the boxing apparatus, as shown in Figures 5 and 6, is exactly the same in construction and use as the apparatus of Figures 1-4.

flange and said securing means,

Having thus described the invention, what is claimed as new and desired to be secured by Letters Patent is:

1. Apparatus for boxing-in impressions, comprising a boxing plate having a flange toward the front end thereof and substantially normal thereto, said plate having impression securing means remote from said flange, said plate also having an opening therethrough between said a deformable member, and means for holding said member seated on said boxing plate and in contact with the front of said flange.

2. Apparatus for boxing-in impressions, as claimed in claim 1 in which said deformable member is recessed along a portion of one edge.

3. A boxing plate for an impression tray having a straight handle, comprising a base member having tray receiving portion and a flange adjacent said portion, said base member having an elongated slot remote from said flange and being imperforate between said slot and said flange, and securing means receivable in said slot for adjustably securing said tray to said base member,

4. A boxing plate for an impression tray having an offset handle, comprising a base member having a tray receiving portion and a flange adjacent said portion, said base member having an elongated slot remote from said flange, said base member also having an opening therethrough between said flange and said slot whereby said impression tray may be seated on said tray receiving portion with the ofiset handle of the tray extending through said opening, and means receivable in said slot for adjustably securing the impression tray to said base member.

References Cited in the file of this patent UNITED STATES PATENTS 28,348 Clark May 22, 1860 95,126 McDonald Sept. 21, 1869 538,204 Traphagen Apr. 23, 1895 2,247,013 Coble June 24, 1941 

